Vc10Tail
Airbus considered an A330 version shorter than the -200 but rejected it on economic grounds.
A 220-seat single-aisle is so much more efficient than a 220-seat widebody that there's really no contest.
As long as you don't mess with the single-aisle by adding new wings, centre wing box, main landing gear and engines etc. And more cost.
I think the 787-8 is the smallest widebody we'll see from now on.